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SEG_LCD

Introduction

The segment LCD, also known as a segmented Liquid Crystal Display (LCD), is a common type of liquid crystal display screen that consists of multiple independent segments or “Zones,” each capable of independently controlling the display of different characters or graphics.

Feature List

This module is divided into two levels of functionality: the bottom layer is the driver-level functions, the the upper layer is the GDC0689 device driver functions implemented based on the driver layer.

Driver Layer Function List

  • Supports LCD screens with a maximum of 8 COM X 32 SEG COM/SEG configuration;

  • Supports various refresh modes: Static, 1/2, 1/3, 1/4, 1/5, 1/6, 1/7, 1/8 duty;

  • Supports various bias voltages: Static, 1/2, 1/3, 1/4 bias;

  • LCD refresh rate can be dynamically configured.

GDC0689 Device Driver Layer Function List

  • Digital display: 6-digit integer or decimal display

  • Time display: Hour and minute display

  • Unit display: “mV” (millivolt), “N” (Newton), “m” (meter), “kg” (kilogram), “g” (gram), “mm” (millimeter), με (microstrain), “kPa” (kilopascal), “MPa” (megapascal), “℃” (Celsius)

  • Icon display: Service icons, power level icons, signal level icons

  • Display all elements

  • Clear display

Function Overview

This module primarily displays time,numbers, units, and icons on the GDC0689 segmented LCD screen.

Hardware Configuration

seg_lcd Configuration (pre-configured)

Configured via Device Tree (DT) modifications.

Main Functions

SEG_LCD Driver Layer Functions

Starting Conditions:

  • Initialize the seg_lcd driver before use

Related APIs:

  • Call wm_drv_seg_lcd_init to initialize the seg_lcd driver

  • Call wm_drv_seg_lcd_register_table to register the seg_lcd display table

  • Call wm_drv_seg_lcd_display_seg to control the display state of specified segments

  • Call wm_drv_seg_lcd_clear to clear all display content

  • Call wm_drv_seg_lcd_deinit to deinitialize the seg_lcd driver

GDC0689 Display Time Function

Starting Conditions:

  • Initialize gdc0689 before use

Relevant Timing APIs:

  • Call wm_gdc0689_init to initialize gdc0689

  • Call wm_gdc0689_display_time to display the current time on the segmented LCD

Result:

  • The current time is displayed on the segmented LCD

GDC0689 Display Numeric Function

Starting Conditions:

  • Initialize gdc0689 before use

Relevant Timing APIs:

  • Call wm_gdc0689_init to initialize gdc0689

  • Call wm_gdc0689_display_integer to display integer values on the segmented LCD

  • Call wm_gdc0689_display_decimal to display decimal values on the segmented LCD

Result:

  • Numbers are displayed on the segmented LCD

GDC0689 Display Unit Function

Starting Conditions:

  • Initialize gdc0689 before use

Relevant Sequence APIs:

  • Call wm_gdc0689_init to initialize gdc0689

  • Call wm_gdc0689_display_unit to display measurement units on the segmented LCD

Result:

  • Measurement Units are displayed on the segmented LCD

GDC0689 Display Icon Function

Starting Conditions:

  • Initialize gdc0689 before use

Relevant Sequence APIs:

  • Call wm_gdc0689_init to initialize gdc0689

  • Call wm_gdc0689_display_service_icon to display the service icon on the segmented LCD

  • Call wm_gdc0689_display_battery_level to display battery level on the segmented LCD

  • Call wm_gdc0689_display_signal_level to display signal strength on the segmented LCD

Result:

  • Icons are displayed on the segmented LCD

Notes

  1. DT configuration needs to be set according to the actual parameters of the segmented LCD;

  2. If using a non-GDC0689 segmented LCD, you need to refer to examples/peripheral/seg_lcd/sample based on the seg_lcd driver and complete the corresponding content display in combination with the segmented LCD datasheet:

    • Step 1. Configure the seg_lcd pins and related parameters through Device Table

    • Step 2. Call wm_drv_seg_lcd_init("seg_lcd"); to initialize the seg_lcd driver

    • Step 3. Define the seg_lcd display table g_seg_lcd_table according to the screen’s datasheet

    • Step 4. Call wm_drv_seg_lcd_register_table(dev, g_seg_lcd_table, sizeof(g_seg_lcd_table) / sizeof(g_seg_lcd_table[0])); to register the seg_lcd display table

    • Step 5. Call wm_drv_seg_lcd_display_seg to encapsulate display functions for various content, you can refer to the implementation in components\driver\src\display\seg_lcd\wm_gdc0689.c

Application Example

API Reference

The API is divided into two parts: one part is the seg_lcd controller driver layer API, and the other part is the GDC0689 device driver API implemented based on the seg_lcd controller driver layer.
SEG_LCD API Reference
GDC0689 API Reference